P Baumer1, H Kele, T Kretschmer, R Koenig, M Pedro, M Bendszus, M Pham. 1. Department of Neuroradiology, Heidelberg University Hospital, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany, philipp.baeumer@med.uni-heidelberg.de.
Abstract
OBJECTIVES: To investigate whether targeted magnetic resonance neurography (MRN) of the brachial plexus can visualise fibrous bands compressing the brachial plexus and directly detect injury in plexus nerve fascicles. METHODS: High-resolution MRN was employed in 30 patients with clinical suspicion of either true neurogenic thoracic outlet syndrome (TOS) or non-specific TOS. The protocol for the brachial plexus included a SPACE (3D turbo spin echo with variable flip angle) STIR (short tau inversion recovery), a sagittal-oblique T2-weighted (T2W) SPAIR (spectral adiabatic inversion recovery) and a 3D PDW (proton density weighted) SPACE. Images were evaluated for anatomical anomalies compressing the brachial plexus and for abnormal T2W signal within plexus elements. Patients with abnormal MR imaging findings underwent surgical exploration. RESULTS: Seven out of 30 patients were identified with unambiguous morphological correlates of TOS. These were verified by surgical exploration. Correlates included fibrous bands (n = 5) and pseudarthrosis or synostosis of ribs (n = 2). Increased T2W signal was detected within compressed plexus portion (C8 spinal nerve, inferior trunk, or medial cord) and confirmed the diagnosis. CONCLUSIONS: The clinical suspicion of TOS can be diagnostically confirmed by MRN. Entrapment of plexus structures by subtle anatomical anomalies such as fibrous bands can be visualised and relevant compression can be confirmed by increased T2W signal of compromised plexus elements. KEY POINTS: • MR neurography (MRN) can aid the diagnosis of thoracic outlet syndrome (TOS). • Identifiable causes of TOS in MRN include fibrous bands and bony anomalies. • Increased T2W signal within brachial plexus elements indicate relevant nerve compression. • High positive predictive value allows confident and targeted indication for surgery.
OBJECTIVES: To investigate whether targeted magnetic resonance neurography (MRN) of the brachial plexus can visualise fibrous bands compressing the brachial plexus and directly detect injury in plexus nerve fascicles. METHODS: High-resolution MRN was employed in 30 patients with clinical suspicion of either true neurogenic thoracic outlet syndrome (TOS) or non-specific TOS. The protocol for the brachial plexus included a SPACE (3D turbo spin echo with variable flip angle) STIR (short tau inversion recovery), a sagittal-oblique T2-weighted (T2W) SPAIR (spectral adiabatic inversion recovery) and a 3D PDW (proton density weighted) SPACE. Images were evaluated for anatomical anomalies compressing the brachial plexus and for abnormal T2W signal within plexus elements. Patients with abnormal MR imaging findings underwent surgical exploration. RESULTS: Seven out of 30 patients were identified with unambiguous morphological correlates of TOS. These were verified by surgical exploration. Correlates included fibrous bands (n = 5) and pseudarthrosis or synostosis of ribs (n = 2). Increased T2W signal was detected within compressed plexus portion (C8 spinal nerve, inferior trunk, or medial cord) and confirmed the diagnosis. CONCLUSIONS: The clinical suspicion of TOS can be diagnostically confirmed by MRN. Entrapment of plexus structures by subtle anatomical anomalies such as fibrous bands can be visualised and relevant compression can be confirmed by increased T2W signal of compromised plexus elements. KEY POINTS: • MR neurography (MRN) can aid the diagnosis of thoracic outlet syndrome (TOS). • Identifiable causes of TOS in MRN include fibrous bands and bony anomalies. • Increased T2W signal within brachial plexus elements indicate relevant nerve compression. • High positive predictive value allows confident and targeted indication for surgery.
Authors: A G Filler; M Kliot; F A Howe; C E Hayes; D E Saunders; R Goodkin; B A Bell; H R Winn; J R Griffiths; J S Tsuruda Journal: J Neurosurg Date: 1996-08 Impact factor: 5.115
Authors: Philipp Bäumer; Markus Weiler; Maurice Ruetters; Frank Staub; Thomas Dombert; Sabine Heiland; Martin Bendszus; Mirko Pham Journal: PLoS One Date: 2012-11-14 Impact factor: 3.240
Authors: Lukas Filli; Marco Piccirelli; David Kenkel; Andreas Boss; Andrei Manoliu; Gustav Andreisek; Himanshu Bhat; Val M Runge; Roman Guggenberger Journal: Eur Radiol Date: 2015-09-15 Impact factor: 5.315
Authors: Avneesh Chhabra; Allan J Belzberg; Gedge D Rosson; Gaurav K Thawait; M Chalian; Sahar J Farahani; Jaimie T Shores; Gene Deune; Shar Hashemi; Shrey K Thawait; Ty K Subhawong; John A Carrino Journal: Eur Radiol Date: 2015-09-22 Impact factor: 5.315